What it means
A general circuit fault on the feedback line that the EGR cooler coolant pump reports speed on. EGR mixes inert exhaust into intake to lower combustion peak temperature — too little raises NOx, too much causes misfires and rough running.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The EGR cooler coolant pump circulates coolant through the exhaust gas recirculation cooler to control exhaust gas temperature. The control module monitors the pump's feedback signal, and this code sets when that feedback circuit is faulty, so the reported pump speed may be missing or unreliable.
Common causes
Most likely first.
- Open or short in pump feedback wiring
- Faulty pump speed or feedback sensor
- Loose or corroded connector
- EGR cooler coolant pump fault
Symptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
How to diagnose it
- Review freeze-frame data and live pump command and feedback readings to see whether the reported feedback disagrees with operation.
- Inspect the EGR cooler pump connector and feedback wiring for corrosion, loose terminals, heat damage, or chafing.
- Check the pump feedback circuit for opens and shorts, following the vehicle wiring diagram.
- Compare the feedback signal with the manufacturer's specification while the pump is commanded under the manufacturer's test procedure.
- If the wiring and feedback signal pass, check the coolant pump and coolant flow through the EGR cooler circuit.
Common fixes
- Secure or clean the pump feedback connector.
- Repair damaged or open feedback wiring.
- Restore coolant level or correct a restriction if testing identifies a flow problem.
- Replace the faulty pump or its feedback sensor if circuit testing isolates the failure there.
Can I keep driving?
Avoid heavy loads if the vehicle pings, loses power, hesitates, or runs roughly, since poor EGR cooler circulation can affect combustion and emissions. Stop if the engine overheats, and have the fault assessed promptly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.